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This is a peer-reviewed, post-print (final draft post-refereeing) version of the following published document:

Lloyd, Rhodri S, Oliver, Jon L, Faigenbaum, Avery D, Howard, Rick, De Ste Croix, Mark B ORCID: 0000-0001-9911-4355, Williams, Craig A, Best, Thomas M, Alvar, Brent A, Micheli, Lyle J, Thomas, D. Phillip, Hatfield, Disa L, Cronin, John B and Myer, Gregory D (2015) Long-Term Athletic Development, Part 2: barriers to success and potential solutions. Journal of Strength and Conditioning Research, 29 (5). pp. 1451-1464. doi:10.1519/01.JSC.0000465424.75389.56

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This is a peer-reviewed, post-print (final draft post-refereeing) version of the following

published document:

Lloyd, Rhodri S and Oliver, Jon L and Faigenbaum, Avery

D and Howard, Rick and De Ste Croix, Mark

B and Williams, Craig A and Best, Thomas M and Alvar,

Brent A and Micheli, Lyle J and Thomas, D.

Phillip and Hatfield, Disa L and Cronin, John B and Myer,

Gregory D (2015). Long-Term Athletic Development, Part

2:barriers to success and potential solutions. Journal of

Strength and Conditioning Research, 29 (5),1451-1464.

ISSN 1064-8011

Published in Journal of Strength and Conditioning Research, and available online at:

http://dx.doi.org/10.1519/01.JSC.0000465424.75389....

We recommend you cite the published (post-print) version.

The URL for the published version is


Disclaimer

The University of Gloucestershire has obtained warranties from all depositors as to their title

in the material deposited and as to their right to deposit such material.

The University of Gloucestershire makes no representation or warranties of commercial

utility, title, or fitness for a particular purpose or any other warranty, express or implied in

respect of any material deposited.

The University of Gloucestershire makes no representation that the use of the materials will

not infringe any patent, copyright, trademark or other property or proprietary rights.

The University of Gloucestershire accepts no liability for any infringement of intellectual

property rights in any material deposited but will remove such material from public view

pending investigation in the event of an allegation of any such infringement.

PLEASE SCROLL DOWN FOR TEXT




NUMBER 1 OF 1

AUTHOR QUERIES

DATE 2/19/ 2015

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ARTICLE JSCR-08-460 2B

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BRIEF REVIEW

LONG-TERM ATHLETIC DEVELOPMENT: PART 2: AU2 BARRIERS TO SUCCESS AND POTENTIAL SOLUTIONS

RHODRI S. LLOYD,1 JON L. OLIVER,1 AVERY D. FAIGENBAUM,2 RICK HOWARD,3

MARK DE STE CROIX,4 CRAIG A. WILLIAMS,5 THOMAS M. BEST,6 BRENT A. ALVAR,7

LYLE J. MICHELI,8,9,10 D. P. THOMAS,11 DISA HATFIELD,12 JOHN B. CRONIN,13,14 AND

AU3 GREGORY D. MYER10,15,16,17

AU4 1Youth Physical Development Unit, School of Sport, Cardiff Metropolitan University, Cardiff, United Kingdom; 2Department

of Health and Exercise Science, The College of New Jersey, Ewing, New Jersey; 3Department of Kinesiology, Temple University,

Philadelphia, Pennsylvania; 4School of Sport and Exercise, University of Gloucestershire, Cheltenham, United Kingdom; 5Children’s Health and Exercise Research Centre, Exeter University, Exeter, United Kingdom; 6Department of Family

Medicine, Division of Sports Medicine, Sports Health and Performance Institute, Ohio State University, Columbus, Ohio; 7Rocky Mountain University of Health Professions, Provo, Utah; 8Department of Orthopaedics, Division of Sports Medicine,

Boston Children’s Hospital, Boston, Massachusetts; 9Harvard Medical School, Boston, Massachusetts; 10The Micheli Center for

Sports Injury Prevention, Boston, Massachusetts; 11Department of Trauma and Orthopaedics, University of Wales, Cardiff,

United Kingdom; 12Department of Kinesiology, University of Rhode Island, Kingston, Rhode Island; 13Sport Performance

Research Institute New Zealand, AUT University, Auckland, New Zealand; 14School of Exercise, Health and Biomedical

Sciences, Edith Cowan University, Joondalup, Australia; 15Division of Sports Medicine, Cincinnati Children’s Hospital

Medical Center, Cincinnati, Ohio; 16Department of Pediatrics and Orthopaedic Surgery, College of Medicine, University of

Cincinnati, Cincinnati, Ohio; and 17Sports Health and Performance Institute, Ohio State University, Columbus, Ohio

ABSTRACT

Lloyd, RS, Oliver, JL, Faigenbaum, AD, Howard, R, De Ste

Croix, M, Williams, CA, Best, TM, Alvar, BA, Micheli, LJ,

Thomas, DP, Hatfield, D, Cronin, JB, and Myer, GD.

Long-term athletic development: Part 2: Barriers to success

and potential solutions. J Strength Cond Res XX(X): 000–

000, 2015—The first installment of this two-part

commentary reviewed existing models of long-term athletic

development. However, irrespective of the model that is

adopted by practitioners, existing structures within competi-

tive youth sports in addition to the prevalence of physical

inactivity in a growing number of modern-day youth may serve

as potential barriers to the success of any developmental

pathway. The second part of this commentary will first

highlight common issues that are likely to impede the success

of long-term athletic development programs and then

propose solutions that will address the negative impact of

such issues.

KEY WORDS youth, children, adolescents, resistance training,

fitness, long-term athlete development

Address correspondence to Rhodri S. Lloyd, [email protected].

00(00)/1–14

Journal of Strength and Conditioning Research

© 2015 National Strength and Conditioning Association

INTRODUCTION

lthough longitudinal data are needed to validate

the design of existing pathways of either talent or

athletic development, it is generally considered

more beneficial to have a progressive system in

situ rather than have no structure at all. However, although

long-term athletic development programs continue to

evolve, a number of contraindicating factors associated with

modern-day lifestyles of youth are becoming an increasing

cause for concern. Enhancing practitioner’s knowledge and

understanding of how exercise prescription for youth should

align with training age, technical competency, growth, mat-

uration, and development is crucial to the progression of our

field (59). However, without addressing current issues facing

the development of today’s youth, practitioners will likely be

working in a compromised environment. Specifically, this

article will examine how long-term athletic development

programs are negatively impacted by (1) inactive lifestyles

of youth, (2) the prevalence of obese and overweight youth,

(3) early sport specialization and associated injury risk, (4)

high workloads of young athletes, and (5) the limitations of

existing education curricula.

OPERATIONAL TERMS

For the purposes of this commentary, the terms youth and

young athletes represent both children (generally up to the

age of 11 years in girls and 13 years in boys) and adolescents

(typically including girls aged 12–18 years and boys aged

VOLUME 00 | NUMBER 00 | MONTH 2015 | 1

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LTAD for all Youth

14–18 years). The term athletic development refers to the

physical development of youth that encompasses the training

of health-, skill-, and performance-related components of fit-

ness. The age-related integration of these components over

time is designed to enhance performance, reduce injury risk,

and enhance the confidence and competence of all youth.

Practitioner denotes an individual responsible for the athletic

development of youth and includes: youth sport coaches,

sports administrators, strength and conditioning coaches,

physical education teachers, athletic trainers, physiotherapists,

and other health care providers. Resistance training refers to

a specialized method of conditioning, whereby an individual is

working against a wide range of resistive loads to enhance

health, fitness, and performance (57). Forms of resistance

training include the use of body weight, weight machines, free

weights (barbells and dumbbells), elastic bands, and medicine

balls. The term physical literacy refers to the ability of an indi-

vidual to use cognitive processes such as anticipation, mem-

ory, and decision-making to help move with poise, economy,

and confidence in a range of physically demanding environ-

ments (131). Fundamental movement skills represent locomotive

(running, skipping, and hopping), manipulative (catching,

throwing, grasping, and striking), and stabilization (balance,

rotation, and antirotation, and bracing) skills (64).

Problem 1: Physical Inactivity

It can be observed from longitudinal data that fitness levels

of youth in general have deteriorated over the past 20–30

years ( 77,10 8,125). Recent evidence now indicates

that a large proportion of children and adolescents

routinely fail to accumulate recommended physical

activity guidelines proposed by leading health authorities (

36,42 ). Of particular concern, researchers have shown that

physical activity levels appear to peak at approximately 6

years of age, after which there is a consistent decline into

adolescence and adulthood ( 126). Additionally, increases in

the amount of time viewing television or playing video

games ( 11), reductions or the removal of time devoted to

recess ( 2), reduced time during the school day for physical

education ( 9 4), reductions in the number of youth who

use active transportation to school ( 107), poor dietary

behaviors ( 14,21,109 ), and insufficient levels of sleep

(37,69,120) are some other lifestyle factors that contribute to

reductions in daily physical activity among youth (86).

Failure to address negative trends in lifestyle factors such

as insufficient sleep or poor dietary behaviors in youth

will undoubtedly reduce or blunt the beneficial effects of

exercise and potentially increase the risk of sport- related

injury. Additionally, researchers have shown that

participating in moderate-to-vigorous physical activity

(MVPA) is positively associated with emotional state in ado-

lescents (115). Combined, these factors will limit, delay, or

postpone athletic development irrespective of the innate tal-

ent of the young athlete. Recognizing that daily physical

activity early in life is a critical component of all long-term

athletic development models, it is imperative that

practitioners responsible for the health and well-being of

youth are cognizant of the importance of these contributing

lifestyle factors and progressively use targeted programming

with appropriate interventions.

Cohen et al. ( 18) indicated that there has been a

recent and sustained decline in the muscular strength levels

of children within the United Kingdom, reporting a 26%

decline in arm strength and a 7% drop in handgrip

strength between 1998 and 2008. Additionally, 1 in 10

children could not support their own body weight on a

wall bar ( 18). The authors suggested that the decline in

strength levels was likely because of reductions in physical

activity levels. Data from other countries shows a similar

trend of strength deficits in youth, highlighting

declines in both handgrip strength and bent-arm hang

performance in Spanish adolescents ( 77 ) and a decline

in the neuromotor fitness of pre- pubescent Dutch

children ( 10 8). Cumulatively, these data indicate that

modern-day youth do not possess sufficient levels of

muscular strength largely due to physical inactivity. This is

an issue that requires immediate attention.

The increased prevalence of deconditioned youth is likely

to have a direct impact on the current requirements and future

structuring of long-term athletic development programs.

Youth require coordinated muscular strength for the success-

ful performance of fundamental movement skills (28,67). It is

also established that fundamental movement skill competency

is associated with long-term engagement in physical activity

(63). Therefore, given the recent decline in both of these

fitness parameters, any long-term strategy should prioritize

the development of muscle strength and motor skill profi-

ciency during the primary school years. It is imperative that

youth engage in training modalities to develop muscular

strength and fundamental movement skills in early childhood

to maximize their modifiable neuromuscular systems (28,92).

These evidence-based guidelines challenge previous athletic

development models (8) and counter preconceived concerns

surrounding structured resistance training for children.

Potential Solutions to the Problem. Considering the existing

levels of inactive youth ( 36,4 2) and that childhood

inactivity typically leads to sedentary lifestyle behaviors in

adolescence and early adulthood (20,100,121,123), it is

imperative that youth engage regularly in strength-

building and skill- enhancing activities at an early age.

Researchers have pre- viously stated that because of the

neural plasticity associated with preadolescence, early

engagement in integrative neuromuscular training (INT)

(which comprises of both health- and skill-related

components of fitness) is instrumental in developing long-

lasting fundamental movement competency and enhanced

physical, psychological, and social development ( 8 4).

Although it is difficult to identify a definitive age at which

to start formalized training, most 7 and 8 year olds are

ready for some type of structured training as part of

fitness recreation, sports practice, or physical education

(31). However, younger children (,7 years of age) should

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Journal of Strength and Conditioning Research | www.nsca.com

still be encouraged to engage with less formalized structured

and unstructured activities (e.g., introductory gymnastics and

playground activities that promote kinesthetic development

and physical literacy). Of note, authors of the 2014 interna-

tional consensus statement on youth resistance training

stated that the child should be emotionally mature enough

to accept and follow instructions and possess competent

levels of balance and postural control ( 57).

Despite global physical activity guidelines recommending

youth accumulate 60 minutes of MVPA per day ( 13 2),

details outlining what should comprise 60 minutes of

MVPA are somewhat general. The WHO ( 13 2)

suggested that daily physical activity guidelines for 5–17

year olds should comprise mainly aerobic exercise; with

higher intensity training that “strengthens muscle and bone,”

being performed 3 times per week. Although these

guidelines offer support for youth to engage with physical

training, it is noteworthy that a greater emphasis is

placed on aerobic exercise in comparison with exercise

that promotes “muscle and bone strengthening” or skill-

building activities. Conversely, practitioners should

acknowledge that developing fundamental movement

skills and muscular fitness within a well-rounded training

program should be the priority for youth, as these

physical qualities ultimately provide the foundations for

MVPA and help to enhance performance and reduce sport-

and physical activity-related injuries. This contention is re-

inforced by research that shows children with high aerobic

fitness and low muscle strength are at a significantly greater

risk of skeletal fracture than youth with higher levels of

muscle strength and lower aerobic fitness ( 17).

Additionally, a recent position statement from the

American Medical Society for Sports Medicine

highlighted that a wealth of research now exists that

shows neuromuscular training can reduce injury risk,

especially injuries to the lower limb ( 27). Clinical

researchers have indicated that the risk of overuse injury

can be reduced in youth populations if children and

adolescents engage with appropriately prescribed and well-

supervised training programs (75,114). Furthermore, it is

purported that training programs inclusive of resistance

training that target risk factors associated with injury risk

(e.g., muscle imbalances) have the potential to reduce over-

use injuries by as much as 50% in youth ( 75,12 8).

T1 Table 1 summarizes the recommended solutions to reduce

the negative impact of physical inactivity on the success of

long-term athletic development programs.

Problem 2: Prevalence of Overweight and Obese Youth

The concept of “underuse” injuries suggests that inactivity

and a lack of preparatory conditioning is a likely risk factor

for the etiology of a number of sports- and physical activity-

related injuries ( 118). In comparison with normal

weight youth, data show that overweight and obese

children and adolescents are twice as likely to experience

an injury when participating in sports or general physical

activity ( 72). Con- sequently, it is suggested that

overweight and obese youth

TABLE 1. Recommendations for reducing physical inactivity in youth.

Starting early in life, all boys and girls should be encouraged to accumulate at least 60 min of MVPA daily as part of active transportation, free play, recreation, physical education, recess and sport

The building blocks of MVPA, namely muscular strength and fundamental movement skills, should serve as the foundation for youth development programs

Practitioner’s need to value both health and skill- related components of physical fitness to avoid negative trajectories in physical and psychosocial well-being in children and adolescents over time

Participation in physical activity should not begin with sports practice and competition but rather evolve out of general preparatory conditioning

are ill-prepared for the physical demands of sports (57), ulti-

mately placing them at an increased risk of injury (

106). Specifically, low fatigue resistance, lack of postural and

neuromuscular control, inadequate strength levels, and

reduced motor control development have all been

proposed as potential mechanisms that increase injury

risk within this population ( 72). Considering the increased

demands of con- trolling an excessively large body mass

in response to the unpredictable and dynamic nature of

sporting activities, overweight and obese youth should

engage in preparatory training, inclusive of both health-

and skill-related fitness components before participating in

organized sport. A similar approach should be taken

for those youth who are of normal weight but inactive.

Of note, normal weight inactive youth may appear ready

to engage in sport; however, their musculoskeletal systems

are likely to require general preparation to meet the

demands of sports practice and competition.

Practitioners and parents alike should recognize that

participation in sport practices will not necessarily provide

enough of a training stimulus to suitably prepare overweight

and obese youth for the loadings encountered within sports.

Researchers have shown that engagement in organized

sports does not guarantee youth attain recommended daily

physical activity guidelines (55), nor enable individual needs

to be addressed, such as excess body mass, muscle imbalan-

ces, dysfunctional movement patterns, and strength and

power deficiencies. Similarly, it has been suggested that the

risk of acute traumatic injury (e.g., ankle sprain or anterior

cruciate ligament injury) is decreased in overweight and

obese individuals who participate in age-appropriate prepa-

ratory neuromuscular conditioning activities ( 57,72).

Impor- tantly, this risk is reduced to a greater extent

when


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LTAD for all Youth

conditioning activities are introduced to youth at an early

age ( 9 2). Collectively, the data support the premise

that a training philosophy based on targeting muscular

strength and fundamental movement skills within a

well-rounded training program is a suitable approach for

obese and overweight youth, much in the same way

training prescription is viewed for normal weight children

and adolescents ( 110). Crucially, to maximize their

participation in physical activity into adulthood, obese,

and overweight youth should be encouraged to adhere

to the hallmarks of existing long- term athletic

development theory (58) as an ongoing lifestyle

commitment.

Potential Solutions to the Problem. Historically, physical activity

interventions aimed at preventing or treating overweight and

obese youth (especially children) have focused on aerobic

exercise (4,110). However, such training modalities can be

problematic in terms of compliance and adherence (110).

Conversely, training interventions inclusive of motor skill

training, strength and power training, and sprint training

have all shown relatively high adherence rates in training

interventions ranging from 8 to 52 weeks in duration

( 71,110,112,113). The increased adherence rates

associated with neuromuscular training for obese and

overweight youth is not surprising given the heightened

imposed demands of handling excess body mass for

prolonged periods of weight- bearing exercise, in

comparison with their normal weight peers. Exposing

overweight and obese youth to aerobic exercise (e.g.,

prolonged periods of running within a physical education

class) may actually increase their risk of injury and

reduce their self-esteem because of the nature of peer

comparison within school-age youth. Researchers have

shown that overweight youth experience greater levels of

criticism during physical activity (35), and such criticism

may limit subsequent engagement in physical activity.

Although peer comparison may be a negative process during

aerobic exercise, in contrast, resistance training offers over-

weight and obese youth the opportunity to outperform their

peers with respect to absolute strength performance. For

example, Deforche et al. ( 2 4 ) showed that overweight

youth performed better than normal weight youth in

activities requiring muscular strength. Although overweight

and obese youth carry excess fat mass, they typically possess

a large fat- free mass also, thus increasing their potential

for absolute strength performance ( 110). Consequently,

overweight and obese youth may be more compliant and

enthused to regularly participate in integrative

neuromuscular-based training programs.

Irrespective of the potential additive benefits of resistance

training programs for overweight and obese youth, practi-

tioners must remain sensitive to the potentially heightened

concerns that these populations may have about their

increased body mass, especially when overweight and obese

youth exercise within the same setting as normal weight

youth. Consequently, practitioners will likely need to

differentiate activities within training sessions (and overall

training programs) to help enable all youth to achieve

success irrespective of their body mass. This approach will

help foster an approach to exercise that encourages self-

improvement and positive social interactions.

Table 2 summarizes key guidelines for practitioners to T2

consider when working with overweight or obese youth.

Problem 3: Early Sport Specialization

Although the injury risks associated with overweight and

obese youth arise from insufficient exposure to sports

and physical activity (72), of growing concern for children

and adolescents are the injury risks associated with excessive

exposure to specific sport(s) (27,46). Early sport specializa-

tion refers to the engagement in intensive year-round train-

ing within a single sport (27) and likely limits the child’s

exposure to a breadth of sporting activities. It is acknowl-

edged that certain sports traditionally favor early specializa-

tion (i.e., gymnastics or figure skating) because of the relative

advantage for a young athlete to perform extreme special-

ized posturing and rotation of the torso and extremities.

However, these young athletes should also be engaged with

an integrative strength and conditioning program focused to

diversify motor skill development and enhance muscle

strength to maximize performance and reduce their relative

risk of injury. Unfortunately, an increasing number of sports

are focusing on exposing children to high levels of formal-

ized sports training at younger ages, even in sports that are

typically classified as late specialization sports (e.g., football

and rugby) without supportive training to enhance motor

TABLE 2. Recommendations for practitioners working with overweight or obese youth.

Create age-related and body size-sensitive opportunities for overweight and obese youth to gain competence and confidence in their general physical abilities before they attempt to participate in sports practice and competition

Encourage overweight and obese youth to participate in supervised resistance training activities because this type of conditioning can enhance a range of physical performance measures and indices of health

Overweight and obese youth are more likely to experience personal success during resistance training sessions in comparison with prolonged continuous aerobic training

Develop innovative opportunities for normal weight and overweight/obese youth to exercise together in a supportive environment in which all participants have an opportunity to experience success and feel good about their accomplishments in a socially supportive environment


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skill competency. Researchers have indicated that youth

who do specialize early in a sport are at an increased risk

of overtraining, overuse injury, and burnout (i.e., stress-

induced withdrawal) ( 1,26,45). Talented youth who

are selected for a sporting team during late adolescence but

have not engaged in age-appropriate conditioning during

their childhood years are more likely to present with poor

fundamental movement skills. For example, Iga et al. (48)

showed that the muscle-loading patterns associated with

youth soccer can lead to alterations in functional

hamstrings to quadriceps strength ratios about the knee,

and that untrained young soccer players presented with

greater quadriceps dominance than those who have

participated in formalized resistance training. Recently,

researchers have proposed that for those athletes who have

specialized in a single sport at an early age, physical training

should concentrate on enhancing generic movement skills

and addressing muscle weakness or imbalances ( 5 9),

instead of being exposed to sport-specific performance-

driven training. Providing progressive and mul- tifaceted

training opportunities for such athletes to develop more

fundamental movement skills may overcome the pro-

pensity for early specializing athletes to be at increased risk

for a sports-related injury, illness, or burnout (45,92).

It is accepted that not all acute injuries are unavoidable in

sport; however, practitioners should be cognizant of risk

factors that may predispose youth to overuse injuries.

Overuse injuries are defined as an injury caused by repetitive

submaximal loading of the musculoskeletal system with

inadequate recovery time for subsequent adaptation

(27,114). It is suggested that the proportion of acute versus

overuse injuries in youth is approximately 50:50; however, it

is feared that the number of overuse injuries is rising (

12). Conditions such as patellofemoral pain ( 65,87),

Osgood– Schlatter disease (41), calcaneal apophysitis (96),

little league elbow ( 5 2 ) and little league shoulder ( 114),

spondylolysis (53), and osteochondritis dissecans ( 101)

are all common overuse injuries seen in children and

adolescents subject to repetitive sports training. As youth

engage earlier in formalized sport and specialize in

sport(s) at younger ages, they may be at increased risk of

experiencing overuse injury ( 45). Of concern, is

researchers have shown that the cycle of reduced activity

after an acute injury can initiate overweight and obesity

markers in youth ( 85).

Irrespective of whether long-term modeling is focused on

developing talent or athleticism, existing literature is

unequivocal that experiencing a range of activities during

childhood is an important component of youth development

(8,22,40,58). From a talent development perspective, researchers

have shown that expert decision-making processes can be

enhanced when young athletes are exposed to a breadth and

depth of sporting experiences (7). Additionally, it was sug-

gested that exposure to a variety of activities where generic

pattern recognition, hand-eye coordination, and decision-

making skills can be developed, will ultimately avoid the

need for early specialization (7). This is exemplified from

the talent development of a young team sport athlete (e.g.,

soccer player). Although soccer may be the primary sport that

the child participates in, they are likely to develop perceptual

and decision-making skills such as visual scanning, anticipa-

tion, and movement pattern recognition from participating in

similar invasion-based sports (e.g., basketball or rugby).

Researchers have also shown that a diversification approach

to sampling many different sports during childhood is optimal

for the development of gross motor coordination (38) and

subsequent athletic performance later in life (56,76). Such

research refutes the misnomer of the “10,000-hour rule,”

which is underpinned by an individual seeking to acquire

expertise in a given activity needs to engage in 10,000 hours

(or 10 years) of deliberate practice, a theory that has been

adopted by previous athletic development models (8). Con-

versely, the research of Moesch et al. (76) and Fransen et al.

(38) shows that accumulating 10,000 hours of specific practice

does not guarantee success and may not be needed to reach

elite performance levels later in life.

From an athletic development perspective, it is important to

expose youth to a variety of movement patterns to ensure

that a child can competently perform a breadth of move-

ment skills in a range of different activities and environments

before specializing in specific movement patterns within

a single sport. Children also need to be introduced to

a breadth of activities as a high proportion of youth who

specialize early will not successfully reach the highest level

of elite sport and will therefore require a requisite level of

athleticism to support lifelong participation in recreational

sport and physical activity. Specifically, a young athlete

should be able to repeatedly produce a range of high quality

movement capacities (e.g., pushing, pulling, rotating, bracing,

jumping and landing, rolling, twisting, hopping, running, and

stabilizing) with requisite force production and attenuation

before being exposed to the rigors of repetitious sport-

specific training.

Potential Solutions to the Problem. Encouraging youth to

participate in a variety of sports during their growing years

can help them develop more diverse motor skills (82). Sports

specialization in youth may underlie reduced diversity in

motor skill proficiency as young athletes focus on sport-

specific skills, while ignoring motor skills developed through

a diversified participation portfolio (38). Although speculative,

if sports specialization occurs too early in children and if

young athletes continue to progress their level of competition,

their opportunities for participation in “fun”-focused age-

related physical activities are likely to be limited, which fur-

ther stifles diversity in motor skills and limits current and

long-term physical activity and health (79). Consequently,

comprehensive motor skill development will be stifled, which

can also increase risk of future injury and potentially reduce

opportunities to achieve optimal sport performance (45,79).

Children who do participate in specialized sport activities

more than 16 hours a week of intense sport-specific focused



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LTAD for all Youth

training should be closely monitored for indicators of

burnout, overuse injury, or potential decrements in perfor-

mance from overtraining ( 8 2). In addition, with the

competitive demands typically higher for athletes

specialized in a single sport, intrinsic risk factors of acute

injury that are higher during competition compared with

training should be monitored during accumulated games,

matches, meets, or tournaments ( 47,8 2). Specialized

athletes involved in intense competition should be allowed

for sufficient recovery time between repeated bouts of

same day ( 10,4 9). Before prolonged competitions,

athletes can also benefit from limiting intense training 48

hours before competition (66). Continued research is needed

to better delineate the threshold competition volume

relative to the emergence of risk factors associated with

overscheduling to better establish formal guidelines to

optimize safe youth sport performance ( 8 2).

Based on the current evidence, we encourage youth to

engage in preparatory INT before the initiation of compet-

itive sport participation. Integrative neuromuscular training

includes general (e.g., strength-building exercises) and spe-

cific (e.g., exercises targeted to address motor control

deficits) conditioning activities that are designed to enhance

both health- and skill-related related fitness ( 13,8 4). In

terms of physical conditioning, youth sport practice and

games may not enable the young athlete to accumulate the

recommended amount of moderate-to-vigorous physical

activity, as a large proportion of time in practice (and even

competition) can be spent in sedentary or low-intensity

physical activities ( 4 3,55). A young athlete’s

participation in sport should evolve out of preparatory

conditioning and instruc- tional practice sessions that

address individual deficits and prepare their motor systems

for the demands of practice and competition ( 57,8 0).

Properly designed INT implemented in preseason and off-

season periods can be especially beneficial to athletes who

have specialized in sports and may not have had adequate

exposure to developmental motor skill activities ( 8 3).

Integrative neuromuscular training provides supportive

conditioning that can reduce injury risk and enhance

performance in all athletes (29,34,82,88–90).

In athletes, it would seem that success at young ages does

not predict long-term success, and in some cases, early sport

specialization may limit the potential to achieve elite status

(82). These data provide support to the concept of early sport

diversification and recognizes that while deliberate play and

practice and formalized sports training is certainly necessary

for success in sports, it is not likely sufficient to achieve max-

imum performance with reduced injury risk without integra-

tion of appropriate long-term athletic training programs (82).

T3 Table 3 summarizes key recommendations to reduce the

negative impact of early sport specialization.

Problem 4: Training Workloads of Youth

For the welfare and well-being of youth, long-term athletic

development pathways must be administered and monitored

carefully by practitioners responsible for the overall development

TABLE 3. Recommendations for practitioners to reduce the risks of early sport specialization.*

Children should be encouraged to participate in a variety of sports during their growing years to influence the development of diverse motor skills

Practitioners should not subscribe to the notion that children and adolescents must accumulate 10,000 h of deliberate practice to achieve sporting expertise

Children who participate in excess of 16 h of specialized sports activities per week should be closely monitored for indicators of burnout, overuse injury, or potential decrements in performance through overtraining

Although all youth should be involved in preparatory INT before the initiation of competitive sport participation, practitioners should ensure that INT is sensibly integrated into an annual plan that also includes periods of reduced sport-specific training to enhance diverse motor skill development and reduce injury risk factors

*INT = integrative neuromuscular training.

of the child or adolescent. Without regular communication

between practitioners, youth may be at risk for excessive

training workloads, contraindicating training methods, insuf-

ficient rest and recovery, and additional nontraining stressors.

Practitioners should also be aware that although children will

often recover more quickly than adults from exercise (espe-

cially high-intensity exercise) (105) because of their underly-

ing physiology, the effects of accumulated fatigue on

neuromuscular control and function after repeated exposure

to exercise in youth remains unclear. Combined, these factors

can theoretically lead to excessive workload accumulation and

youth experiencing nonfunctional overreaching (6), overtrain-

ing syndrome (74), or burnout (61).

Data on youth from the United Kingdom have shown that

a relatively high proportion of young athletes have reported

experiencing overtraining or nonfunctional overreaching (68).

Specifically, 29% of 376 young athletes competing at club to

international level from 19 different sports reported experienc-

ing overtraining or nonfunctional overreaching at least once

(68). Although Matos et al. (68) indicated that overtraining or

nonfunctional overreaching were not solely a result of physical

training load, it is likely that a long-term development plan

that fails to allow sufficient time for recovery, adaptation, and

natural growth processes will increase the likelihood of nega-

tive health outcomes for youth (23). When considering the

overall workload of the child or adolescent, it is imperative

that practitioners value the quality of practice and competition,

as opposed to the quantity of training or competition time.

Researchers have shown that parental or coach-led

pressure can positively or negatively influence youth ( 9

9).


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Such external pressure to perform in multiple competitions

or to train or play when injured to make selection for higher

level competitions (i.e., national team rosters or securing

professional contracts) can also contribute to the risk of

intolerable workloads. Consequently, balancing exposure

between competitive events and time dedicated towards

physical preparation must be an integral component of any

long-term athletic development model.

Possible Solutions to the Problem. The objective of the strength

and conditioning coach is to carefully manipulate training

loads to achieve long-term adaptations in physical perfor-

mance. Although practitioners will intuitively adopt their

preferred philosophy of periodization (e.g., progressive cycling

of various aspects of training), it is generally accepted that

planning sequential blocks of training is crucial to elicit the

greatest adaptive response. Recently, Haff (44) suggested that

for young children entering a long-term athletic development

model, the majority of their time engaged within the system

should be devoted to general preparatory training and the

development of fundamental movement skills. However, as

the child moves through the long-term athletic development

pathway, a greater emphasis should be placed on competition,

so that by the time they reach adulthood (approximately

20 years of age), they will spend 25–35% of their time in

training and 65–75% of their time in competition (44).

Although these ratios are estimations and do not account

for individual differences, the notion of prioritizing general

preparatory training and developmental practices during the

early stages of childhood is essential. Such an approach will

hopefully avoid excessive competitive workloads and negative

experiences, which may ultimately lead to premature disen-

gagement from the sport during early adolescence (98). Such

an approach should also help ensure the holistic development

of youth (97). Interestingly, Matos et al. (68) reported that

level of competition was significantly correlated with the inci-

dence of nonfunctional overreaching or overtraining; and

therefore, practitioners working with youth must ensure that

long-term athletic development is driven by process (athlete-

centered) as opposed to outcomes (results-oriented), espe-

cially at the younger ages of competition.

The need for a comprehensive approach that is consid-

erate of all demands to long-term athletic development is

emphasized for youth who participate in multiple sports.

The design of training programs for single-sport athletes will

typically include an appropriate phase of physical prepara-

tion before the onset of a competitive phase. However, for

youth who participate in multiple sports, competitive

seasons may run synonymously (i.e., 2 winter sports) or

overlap (e.g., a fall, winter, and spring sport). Irrespective of

the arrangement of the seasons, practitioners must avoid the

temptation of solely focusing on the loading stimulus during

training phases and ensure that adequate transition and

preparation phases exist within the overall long-term athletic

development plan. Enforced transition/preparation phases

from sport-specific training are also essential to ensure that

the child has sufficient time to rest and recover and to enable

normal growth and maturation processes to occur. These

phases are also important to safeguard against the negative

effects of accumulated fatigue and potential risks of overuse

injury. An example of this is apparent in recent recommen-

dations, whereby young baseball pitchers are encouraged to

pitch for no more than 8 months within a 12-month time

frame to reduce the risk of overuse injury in the shoulder (

3). General preparation should also be viewed as an

opportunity to regain, or improve on, precompetition levels

of fitness that would typically have plateaued or decreased as

a result of the demands of the competitive season. For

example, during an enforced transition/preparation phase,

a practitioner may need to rectify muscle imbalances or

decrements in motor skill proficiency that have developed

through exposure to competition and reduced

opportunities for preparatory conditioning. Youth who

specialize in a single sport should be encouraged even

more to participate in planned periods of enforced

preparation to allow exposure to isolated and focused

INT, to enhance diverse motor skill development, and

reduce injury risk factors ( 8 2). Such an approach re-

quires a high degree of cohesion between practitioners of

different sports/teams, which might be challenging. How-

ever, for the long-term welfare and well-being of the child or

adolescent adequate preparation time must be viewed as

a critical component of any athletic development model.

Several prominent international organizations have recom-

mended that the training of youth athletes should be

monitored to avoid the negative consequences of excessive

training (1,27,81). Whether these recommendations are being

implemented is unknown, but the continued reporting of con-

sistent levels of staleness, burnout, and overtraining in youth

sports suggest that more needs to be done to protect youth

athletes (50,68,104). Part of the problem is the difficulty

of identifying initial symptoms of overtraining in youths.

Prolonged impairments in performance are a defining charac-

teristic of overtraining in adults (73). In youth growth, matu-

ration and development may obscure the ability to identify

decrements in performance caused by overtraining. Perfor-

mance decrements lasting months or longer may be caused

by a naturally occurring period of adolescent awkwardness, as

has been noted in youth soccer players (102). Conversely, over-

training may cause impaired responsiveness to training but

with natural growth and maturation processes still allowing

some level of improvement or maintenance of performance,

masking the negative consequences of overtraining. Supporting

the difficulty of identifying physical symptoms of overtraining

the American Medical Society for Sports Medicine (27) have

stated that there seems to be more of a psychological compo-

nent to burnout and attrition in youth sports.

A holistic approach should be adopted to monitoring youth

athletes, considering both physical and psychosocial perspec-

tives. In addition to performance decrements, the most

prevalent physical symptoms association with nonfunctional



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LTAD for all Youth

overreaching and overtraining in youth sports include loss of

appetite, predisposition to injury, frequent tiredness, inability

to cope with training loads, frequent respiratory infections,

heavy muscles, and sleep problems (68). Although the most

prevalent psychological symptoms include apathy, feeling

intimidated by opponents, bad mood, often feeling sad, lack

of confidence in the future and in competition (68). Coaches

should educate youth athletes and their parents to be aware of

such symptoms, build a good rapport with their athletes to

help identify potential symptoms, have robust monitoring sys-

tems in place to allow early detection of overtraining, and

have appropriate strategies to deal with suspected cases of

overtraining. As an example of psychological monitoring,

the profile of mood state has been widely used to identify

overtraining in adult athletes and a condensed, 24-question

version, has been validated for use with adolescent popula-

tions (124).

Key considerations for practitioners to consider when

managing the training workloads of youth are presented in

T4 Table 4.

Problem 5: Current Physical Education Provision

During childhood, the neuromuscular system is highly

“plastic” (33,92) and is amenable to adaptation owing to

the peaking of brain maturation rates (6–8 years and 10–12

years) ( 10 3), synaptic pruning ( 15), and overall

strengthening of the synaptic pathways (16). It has also

been established

TABLE 4. Recommendations for managing training workloads of youth.

For young children entering sport(s) development pathways, focus should be geared towards preparatory conditioning and fun-based activities, with a reduced focus on competitive fixtures. As children mature and develop towards adulthood, the ratio between training and competition should change to reflect a greater focus on competitive performance

Children who engage with competitive sports should follow a long-term athletic development plan than includes preparatory conditioning and transition mesocycles to facilitate recovery, growth, and to reduce the risk of overuse injury

During preparation and transition mesocycles, practitioners should endeavor to address any physical limitations (e.g., reduced muscle strength and power or decrements in sprint mechanics) or common injury risk factors (e.g., muscle imbalances, inefficient landing mechanics)

The process of monitoring training workloads must be holistic in nature and procedures for identifying overtraining in adults should not necessarily be applied to youth

that fundamental movement skill mastery and motor pro-

ficiency are positively associated with long-term engagement

in physical activity ( 116,117,133 ), and that childhood is

an opportune time for motor skill development. Research

also shows that muscular strength is important for motor

skill performance (9,19,32,60,122,127), and that children

can make worthwhile improvements in muscular

strength after appropriate training interventions (9).

Consequently, because of the neural plasticity associated

with childhood and the responsiveness to motor skill and

resistance training, a strong focus of physical education

curricula should be based on developing a breadth and

depth of movement skills and requisite levels of muscular

strength ( 5 8).

Notwithstanding the awareness of substandard levels of

current health and fitness of modern-day youth, the lack of

robust governmental strategies for physical activity within

the education sector remains a critical cause for concern

(130). Not all modern physical education curricula exclu-

sively involve the enhancement of physical fitness and

have become more diverse in terms of subject content and

required learning outcomes. For example, within the United

Kingdom, primary school in addition to pupils being taught

to play competitive sports, learn dance and rhythmic move-

ment patterns, and participate in outdoor and adventurous

activities; they must also be taught to develop critical think-

ing skills and learn to use information technology within the

physical education setting (25). Despite modern-day policies

leading to an increased demand on physical education teach-

ers, it should be noted that the term “physical education”

represents the educating program related to the physique of

the human body and should encourage psychomotor learn-

ing in a variety of settings that promote health and exercise

(5). Therefore, even with such a broad range of curricula

requirements to satisfy, physical education programs must

retain a central tenet of offering youth the opportunity to

engage in meaningful physical activity that enhances both

health and skill-related components of physical fitness.

Because childhood represents a unique opportunity to take

advantage of a highly plastic neuromuscular system, expo-

sure to daily primary school physical education curricula

would seem to be a critical time frame in which to develop

athleticism, promote psychosocial development, and instill

motivation for lifelong engagement in regular physical

activity.

Despite the obvious role for the education sector to teach

and develop health and skill-related fitness in school-age

youth, researchers have shown that current education

systems are failing to develop appropriate standards of

fitness (77,108,119). For example, an examination of the

national curricula for physical education within the United

Kingdom shows that there is minimal reference to age-

appropriate motor skill development and resistance training

for school children, especially for primary school education.

Furthermore, in the United Kingdom, it is recognized that

primary school teachers are poorly prepared through their


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teacher training programs to teach physical education ( 51), of appropriately prescribed physical development interven- and it has been suggested that the statutory requirements for tions on the health and fitness of youth (29,54,62), it would physical education have often not been achieved ( 51). It seem that existing education structures require a dramatic would seem that limited subject knowledge is often the pri- overhaul to enhance their capacity to reverse the cascading mary explanation for inadequate standards of physical edu- effects of physical inactivity and its associated negative cation teaching in primary schools within the United health outcomes ( 3 2,130). Kingdom ( 95). Within existing physical education curricula, what could

Similar negative trends are evident within the United be viewed as “athletic development” is often termed health- States, with more than half of all states permitting school related exercise (HRE) and is typically delivered in discrete districts to allow students to substitute other activities for units of work across a single school term (95), often by their required physical education classes ( 9 3), and 59% practitioners without the relevant expertise in long-term ath- of states allowing required physical education credits to letic development. These units of work are then replaced be earned through online computer-based courses ( 9 4). with more traditional units of seasonal sports (e.g., rugby, The inability of existing education curricula to appropriately soccer, or hockey). Adopting such a short-term policy will prepare children for the demands of recreational fitness or blunt the continual development of athleticism of youth, will sporting activities was reflected in recent data examining the likely enable some form of detraining to ensue, and not preparedness of college freshmen for the rigors of college- facilitate the correction of key injury risk factors (e.g., poor based strength and conditioning ( 12 9). The researchers landing mechanics or lack of postural stability). Researchers showed that current college strength and conditioning have shown that significant improvements in physical fitness coaches believed the areas of athleticism requiring the great- can be achieved from approximately 15 minutes of INT est improvement of college freshmen were lower extremity twice weekly ( 30,2 9). Therefore, some form of targeted ath- strength, weightlifting technique, core strength, and overall letic development training should be creatively incorporated flexibility ( 12 9). It is reasonable to suggest that if education into all physical education classes (e.g., dynamic warm-up sectors possess more highly skilled practitioners in the pro- activities) and not just limited to independent blocks of HRE vision of athletic development, the number of youth entering teaching. college-based programs with substandard levels of athleti- The development of athletic potential in school-age youth cism could be reduced. should be viewed as a long-term process. To adopt some

Irrespective of the existing concerns with the provision of form of periodization to the school physical education physical education curricula, a recognized and certified system, practitioners should view the school career of youth continued professional development (CPD) pathway does as a sequence of multiyear plans: (1) primary school years not currently exist for practitioners to enhance their and (2) years spent in secondary education. By integrating knowledge base and practical skill sets within the field of a long-term periodized approach within the school system, youth athletic development. Furthermore, it is likely that practitioners can structure sequential annual curricula to a number of physical education teachers working within progressively build on the athletic potential of all youth. schools (especially primary schools) may not be willing or Within each school year, practitioners can then design each motivated to actively participate in continued CPD oppor- term to serve as a structured mesocycle (typically 4–8 tunities related to long-term athletic development, which weeks), with each teaching week representing a structured poses a very real problem if existing education curricula are microcycle (5–7 days). Although such an approach may ini- to change to address the current syllabus that is delivered to tially seem complex and unrealistic, using this type of perio- school-age youth. For example, recently, it has been shown dized approach to school-based physical education should that high school physical education teachers’ and youth offset the chances of exposing youth to isolated blocks of sport coaches’ knowledge and understanding of youth resis- HRE that fails to produce long-term gains above and tance training is deficient and not consistent with the rec- beyond that of growth and maturation. ommended guidelines (39,70). Consequently, it is imperative Of interest to the practitioner is how philosophies from that physical education teacher training programs provide athletic development modeling ( 5 8 ) can be integrated within trainee teachers with the relevant curriculum to ensure that, school-based physical education. Initially, practitioners at least, newly qualified teachers possess up-to-date knowl- working within a school system should ensure that children edge and the necessary skill sets to deliver appropriate ath- are exposed to varied practices that focus on developing letic development curricula to all youth. a broad range of athletic motor skill competencies (AMSC

( 78); Figure 1) and appropriate levels of muscle strength. F1 Possible Solutions to the Problem. Cumulatively, it would seem

that the content of existing education curricula and the

knowledge of practitioners responsible for the delivery of

such curricula are suboptimal for long-term physical devel-

opment in youth. Despite the short- and long-term benefits

Such an approach is illustrated within the Composite Youth

Development (CYD) model presented in part 1 of this com-

mentary. Within the primary education sector, such practice

should be delivered and developed through exploratory

activities that stimulate creativity in the child, which, in turn,



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LTAD for all Youth

Figure 1. Athletic motor skill competencies (reprinted from Moody et al. ( 78)). Adaptations are themselves

works protected by copyright. So in order to publish this adaptation, authorization must be obtained both from the

owner of the copyright in the original work and from the owner of copyright in the translation or adaptation.

primary physical education

should be viewed as an oppor-

tunity to teach motor skills that

can facilitate more advanced

training modes at later stages

of development. For example,

a teacher should attempt to

develop fundamental move-

ment patterns and body weight

management ability in young

children (e.g., through the

use of basic gymnastic type

activities) that will act as the

foundations for more complex

activities (e.g., weightlifting

exercises, advanced plyomet-

rics and high velocity, speed,

and agility activities). Within

the primary school sector

where physical education

budgets may be limited, practi-

tioners working with youth

should realize that expensive

equipment is not necessarily

required to develop competent

motor skill proficiency and pri-

mal levels of muscle strength in

young children. For example,

there are many different forms

of resistance that can be used

increases enjoyment and motivation. Teachers should avoid

relying purely on sport-specific skill development or low-

intensity and prolonged aerobic exercise. Additionally,

TABLE 5. Recommendations for practitioners working within educational systems.

Children should receive targeted integrative neuromuscular training wherever possible within each lesson

“Athletic development” should not be constrained to aspiring young athletes or independent blocks of health-related exercise for a single school term

Wherever possible, schools should adopt a long-term periodized approach to physical education to ensure that youth have the best opportunity to make continued worthwhile changes in physical fitness

The primary school years offer a unique opportunity to develop fundamental motor skills, enhance muscular strength, and improve physical literacy. This should be recognized within primary school curricula, whereby youth should be provided with regular opportunities to develop such qualities within a creative and supportive learning environment

as on overload stimulus to develop muscle strength (e.g.,

body weight, manual resistance, elastic bands, medicine

balls), all of which have proven successful in training inter-

ventions in youth (57).

Table 5 provides recommendations for practitioners to T5

consider when working within existing educational systems.

NEED FOR AN INTERNATIONALLY RECOGNIZED YOUTH

TRAINING CERTIFICATION

Irrespective of which model is adopted by practitioners, the

success of any youth training plan is largely based on the

suitability of the program design and the pedagogical skills of

the practitioner(s) responsible for its delivery (33,84).

Although existing models have undoubtedly furthered the

cause of youth training, the depth of understanding of

growth and maturation influences on physical performance

and how these influence program design remains highly

varied among practitioners. Consequently, an internationally

recognized youth training certification should be developed

and endorsed by professional organizations to help ensure

the provision of safe and effective exercise prescriptions for

children and adolescents. Importantly, such a certification

process would require a practitioner to be assessed for

knowledge and understanding of key concepts surrounding

pediatric exercise science, the ability to design, coach and


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modify developmentally appropriate training programs, and

pedagogical skills to ensure that scientific principles can be

translated into practice in a child-focused approach. Such

a certification process should become accepted practice,

not just within sporting administrations but also in the edu-

cation and health care sectors, especially in light of recent

trends in MVPA and the increasing prevalence of sport- and

physical activity-related injuries in youth. The concept of an

internationally recognized certification is particularly impor-

tant given the existing knowledge and awareness of current

guidelines for youth-specific exercise prescription within the

sport, education, and health care systems (32,39,111). Irre-

spective of whether practitioners are working with youth in

competitive sports, recreational activity, daily physical edu-

cation classes or organized health-based interventions, an

internationally recognized certification is deemed as an

important developmental step to ensure that philosophies

and practices of long-term athletic development are geared

towards ensuring the holistic development of all youth.

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